d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Add sysctl/tunables for various metaslab variables.

Browse Source
This commit is contained in:
Pawel Jakub Dawidek 2013-09-05 00:53:01 +00:00
parent 4877522e76
commit 7e473ea146
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=255226
1 changed files with 33 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
sys/cddl/contrib/opensolaris/uts/common/fs/zfs/metaslab.c
View File

@ -32,6 +32,9 @@
#include <sys/vdev_impl.h>
#include <sys/zio.h>
SYSCTL_DECL(_vfs_zfs);
SYSCTL_NODE(_vfs_zfs, OID_AUTO, metaslab, CTLFLAG_RW, 0, "ZFS metaslab");
/*
* Allow allocations to switch to gang blocks quickly. We do this to
* avoid having to load lots of space_maps in a given txg. There are,
@ -46,6 +49,10 @@
uint64_t metaslab_aliquot = 512ULL << 10;
uint64_t metaslab_gang_bang = SPA_MAXBLOCKSIZE + 1; /* force gang blocks */
TUNABLE_QUAD("vfs.zfs.metaslab.gang_bang", &metaslab_gang_bang);
SYSCTL_QUAD(_vfs_zfs_metaslab, OID_AUTO, gang_bang, CTLFLAG_RWTUN,
&metaslab_gang_bang, 0,
"Force gang block allocation for blocks larger than or equal to this value");
/*
* The in-core space map representation is more compact than its on-disk form.
@ -61,17 +68,19 @@ int zfs_condense_pct = 200;
* allocations on that device.
*/
int zfs_mg_alloc_failures = 0;
SYSCTL_DECL(_vfs_zfs);
SYSCTL_INT(_vfs_zfs, OID_AUTO, mg_alloc_failures, CTLFLAG_RDTUN,
TUNABLE_INT("vfs.zfs.mg_alloc_failures", &zfs_mg_alloc_failures);
SYSCTL_INT(_vfs_zfs, OID_AUTO, mg_alloc_failures, CTLFLAG_RWTUN,
&zfs_mg_alloc_failures, 0,
"Number of allowed allocation failures per vdev");
TUNABLE_INT("vfs.zfs.mg_alloc_failures", &zfs_mg_alloc_failures);
/*
* Metaslab debugging: when set, keeps all space maps in core to verify frees.
*/
static int metaslab_debug = 0;
TUNABLE_INT("vfs.zfs.metaslab.debug", &metaslab_debug);
SYSCTL_INT(_vfs_zfs_metaslab, OID_AUTO, debug, CTLFLAG_RWTUN, &metaslab_debug,
0,
"Metaslab debugging: when set, keeps all space maps in core to verify frees");
/*
* Minimum size which forces the dynamic allocator to change
@ -80,6 +89,11 @@ static int metaslab_debug = 0;
* aggressive strategy (i.e search by size rather than offset).
*/
uint64_t metaslab_df_alloc_threshold = SPA_MAXBLOCKSIZE;
TUNABLE_QUAD("vfs.zfs.metaslab.df_alloc_threshold",
&metaslab_df_alloc_threshold);
SYSCTL_QUAD(_vfs_zfs_metaslab, OID_AUTO, df_alloc_threshold, CTLFLAG_RWTUN,
&metaslab_df_alloc_threshold, 0,
"Minimum size which forces the dynamic allocator to change it's allocation strategy");
/*
* The minimum free space, in percent, which must be available
@ -88,22 +102,37 @@ uint64_t metaslab_df_alloc_threshold = SPA_MAXBLOCKSIZE;
* switch to using best-fit allocations.
*/
int metaslab_df_free_pct = 4;
TUNABLE_INT("vfs.zfs.metaslab.df_free_pct", &metaslab_df_free_pct);
SYSCTL_INT(_vfs_zfs_metaslab, OID_AUTO, df_free_pct, CTLFLAG_RWTUN,
&metaslab_df_free_pct, 0,
"The minimum free space, in percent, which must be available in a space map to continue allocations in a first-fit fashion");
/*
* A metaslab is considered "free" if it contains a contiguous
* segment which is greater than metaslab_min_alloc_size.
*/
uint64_t metaslab_min_alloc_size = DMU_MAX_ACCESS;
TUNABLE_QUAD("vfs.zfs.metaslab.min_alloc_size",
&metaslab_min_alloc_size);
SYSCTL_QUAD(_vfs_zfs_metaslab, OID_AUTO, min_alloc_size, CTLFLAG_RWTUN,
&metaslab_min_alloc_size, 0,
"A metaslab is considered \"free\" if it contains a contiguous segment which is greater than vfs.zfs.metaslab.min_alloc_size");
/*
* Max number of space_maps to prefetch.
*/
int metaslab_prefetch_limit = SPA_DVAS_PER_BP;
TUNABLE_INT("vfs.zfs.metaslab.prefetch_limit", &metaslab_prefetch_limit);
SYSCTL_INT(_vfs_zfs_metaslab, OID_AUTO, prefetch_limit, CTLFLAG_RWTUN,
&metaslab_prefetch_limit, 0, "Maximum number of space_maps to prefetch");
/*
* Percentage bonus multiplier for metaslabs that are in the bonus area.
*/
int metaslab_smo_bonus_pct = 150;
TUNABLE_INT("vfs.zfs.metaslab.smo_bonus_pct", &metaslab_smo_bonus_pct);
SYSCTL_INT(_vfs_zfs_metaslab, OID_AUTO, smo_bonus_pct, CTLFLAG_RWTUN,
&metaslab_smo_bonus_pct, 0, "Maximum number of space_maps to prefetch");
/*
* Should we be willing to write data to degraded vdevs?